Research productivity in many different biomedical disciplines will increase significantly when novel "custom made" animal models routinely become available. Hence, the long term objectives of this proposal include the creation of new laboratory models that have biological properties fundamentally different from their respective naturally occurring animal species. These unique models could be produced by directly electrofusing individual cells having particular properties to intact tissue of anesthetized animals with the aid of a newly designed and constructed scientific instrument. Such an instrument can become a reality after a number of important parameters have been characterized. In this regard, the following hypothesis is presented. "A defined set of combined electromechanical parameters exist or the optimal rapid, efficient electrofusion of individual cells to intact tissue in vivo". The specific aims in this proposal are limited in scope to testing this hypothesis as follows: 1) to examine the necessity of AC dielectrophoresis for cell-tissue alignment in vivo under defined mechanical pressures and DC electrical fusion fields; 2) to explore the role of DC fusion fields in vivo under defined mechanical pressures and AC dielectrophoretic fields (if required); 3) to integrate the most effective combined electromechanical conditions for optimizing in vivo cell-tissue electrofusion; and 4) to construct a prototype instrument having unique probes whose design and operation are based upon optimal electromechanical parameters as defined by experimentation. Newly developed instrumentation will allow us to achieve our long term objectives of creating novel animal models for accelerating biomedical research productivity in many different areas. These areas include, but are not limited to, immunology, infectious diseases, experimental therapeutics, cancer research, ophthalmology, embryology, and possibly even wound research and gene therapy.